Machine for making a compressor blade



April 15, 1958 E. P. WARNKEN MACHINE FOR MAKING A coMPREssdR BLADEOriginal Filed Oct. 14. 1952 2 Sheets-Sheet 1 I INVENTOR. E L MEI? P.Map/mew .Atfys.

April 15, 1958 E. P. WARNKEN 2,830,647

MACHINE FOR MAKING A COMPRESSOR BLADE Original Filed Oct. 14. 1952 2Sheets-Sheet 2 INVENTOR. Euv/ER P MAW/(EN United States Patent MACHINEFOR MAKING A CONIPRESSOR BLADE Original application October 14, 1952,Serial No; 314,698. Divided and this application December 9, 1955,Serial No. 552,128

3 Claims. (Cl. 154-1) This invention relates to compressor blades forthe rotors of axial-flow air compressors, and more particularly to amachine for forming such blades.

This is a division of my co-pending application Serial No. 314,698 filedOctober 14, 1952.

An object of this invention is to provide a resin-impregnated laminatedrotor blade having a main molded blade portion and a thickened portionat one end thereof by means of which the blade may be mounted in placeon the rotor of an air compressor.

A further object of this invention is to provide a blade formed from aplurality of laminations mounted one on the other but separated into twoportions at one end of the blade, so that the end of the blade isthickened.

A further object of this invention is to provide a compressor bladehaving diverging end portions between which is disposed a molded plugwhich holds the laminations apart at the end to formv a strong thickenedroot or end portion.

A further object of this invention is to provide a machine formanufacturing such a blade having two main dies for forming the mainportion of the blade and an intermediate die whichextends betweenportions of laminations during molding to cause the laminations todiverge at one end of the blade to form the thickened end.

The above and other objects and features of this invention will in partbe apparent and will in part be obvious from the following detaileddescription and the drawings, in which: t

Figure 1 is a perspective view of a compressor blade constructed inaccordance with an embodiment of this invention with a root-holdingmember being shown mounted on the blade;

Fig. 2 is a perspective view of the blade in the form assumed whenremoved from a mold and before excess material and flash is trimmedtherefrom;

Fig. 3 is a view in section taken along line IIIIlI in Fig. 1;

Fig. 4 is a diagrammatical view in section showing an assembly oflaminations in condition for molding to form the blade shown in Fig. 1;

Fig. 5 is a perspective view of a block which spaces the laminations atone end of the blade;

Fig. 6 is a view in section showing a machine for molding the blade;

Fig. 7 is an enlarged view in section taken along a line VII-Vl'l inFig. 6; and

Fig. 8 is a diagrammatic view in section taken along a line VIII-VIII inFig. 4;

Fig. 9 is a plan view of a root-holding member used in mounting theblade.

In Fig. 1 of the drawings a rotor blade 9 for an axia1- fiow aircompressor is shown. Blade 9 includes an impeller section 10 having athickened end or root portion 11 on which is mounted a member 13 bymeans of which the blade may be mounted on and secured to the rotor ofthe air compressor.

Patented Apr. 15, 1958 fabric 14 which are impregnated with athermosetting resin. At the root end of the blade, the layers of fabricare separated as in Fig. 4, by a cross piece 15 composed of a pluralityof superposed layers of glass fabric impregnated with the samethermosetting resin as layers14. The tip of the blade portion 10 and theends of the separated layers at the root are secured by staples 16. Theimpregnated layers of fabric and the cross piece 15 are placed in asuitable mold or press and heated to set the resin and form a rigidblade as shown in Fig. 2. The cross piece 15- being of resin impregnatedlaminated glass fabric sheets, it fuses into the root layers or sheetsto form a strong compact root section.

After the resin has been set, the root of the blade is cut off as alongthe line AA' and the flash is trimmed off on lines BB, CC and D-D toform a finished blade as in Fig. l.

After the blade has been finished, the tip of the blade is insertedthrough the opening 17 in member 13 and the latter is slid back againstthe root.

In the diagram, only a limited number of laminations 14 are shown.However, it is to be understood that the blade forming laminations maybe of any appropriate number. For example, I use approximately twelve tofourteen laminations in forming a compressor blade having its thickestpart approximately one-eighth of an inch thick. The glass woollaminations may be of the type described in my co-pending applicationSerial No. 154,333 filed April 6, 1950, now U. S. Patent 2,746,514 withinner laminations of relatively coarse glass wool cloth while theoutermost laminations are of relatively closely woven glass wool cloth.

A machine for use in molding the blade is illustrated in Figs. 6 and 7.The machine includes a framework 21 on which is mounted a base plate 22.Plate 22 carries a main stationary die 23 and posts 24 and 26 atopposite ends of stationary die 23. Posts 24 and 26 form guides for amovable platen 27. Platen 27 carries a main movable die '28 which has alower or molding face 28a adapted to co-operate with the upwardly facingmolding face of die 23.

The root end of the blade is formed around an intermediate die 29. Die29 projects between main stationary die 23 and main movable die 28. Asshown in Fig. 6, the left hand ends of the main dies diverge on oppositesides of intermediate die 29. Intermediate die 29 is triangular invertical section so that the end portions of the elongated laminationsdiverge as the sides of a triangle when the blade end is formed aroundthe intermediate die.

Intermediate die 29 is vertically reciprocable and is mounted in a track31 (Fig. 7) in a guide pillar 32. Track 31 is formed as shown tointerlock with a dovetail 32' on the intermediate die to hold the die 29in alignment with the main dies as the intermediate die slides up anddown the track. Downward movement of intermediate die 29 is arrested bya spring 33 (see Fig. 6). Spring 33 holds intermediate die 29 normallyspaced at a sufiicient distance above main stationary die 23 so that anassembly of laminations such as that shown in Figs. 4 and 6 can readilybe inserted between the dies with portions 33' and 33" of thelaminations projecting on opposite sides of intermediate die 29 and plug15 adjacent the right hand end of intermediate die 29 (see Fig. 6).

Movable platen 27 and main movable die 29 can be driven downwardlytoward the stationary and intermediate dies by means of an appropriatehydraulic cylinder 34 and pressure connections (not shown). When movableplaten 27 and movable die 29 are brought down upon the laminations, thelaminations are molded between the dies to form the intermediate bladeconstruction shown in Fig. 2. During molding, intermediate die 29 ispushed downwardly against the spring 33 so that, in effect, intermediatedie 29 floats between the main dies.

As the blade is molded, the cross piece 15 is caused to flow between theportions of the elongated laminations 14 so that the cross piece or plugbecomes an integral part of the finished blade, firmly holding thelamination portions' 33" and 33 apart at the root end of the blade.

.The root end of the blade is sufficiently strong that it is unnecessaryto have any fixed connections between member 13 (Fig. 1) and the blade.The member 13 is made of metal, such as aluminum. The member 13 isslidably received upon the impeller section of the blade 9. The opening17 in member 13 tapers, as shown in Figs. 1 and 9, and the thickenedroot portion of the blade 9 engages the sides of the opening 17 so thatthe blade is firmly gripped by the member 13.

The blade and the machine for forming the blade described above andillustrated in the drawing are subject to structural modificationwithout departing from the spirit and scope of the appended claims.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

l. A machine for molding an airfoil blade 'which comprises a pair ofmain dies having elongated opposed die cavities, the cavities at one endof the dies having wall surfaces that diverge at an acute angle to eachother, means for reciprocating at least one of the main dies toward andaway from the other main die, a track adjacent the diverging wallsurfaces of the main die cavities and extending parallel to thedirection of reciprocation of the reciprocating main die, anintermediate die mounted for reciprocation on said track, guide membersextending parallel to said track between the main dies to guide themovable main die for movement parallel to movement of the intermediatedie, said intermediate die having a wedge-shaped portion projectingcantilever-fashion between said diverging wall surfaces, the oppositefaces of the wedge-shaped portion being substantially parallel to andadjacent the diverging wall surfaces of the main dies, and a springurging the intermediate die to a position between and in spaced relationto the main dies when the main dies are open, the spring yielding whenthe main movable die is closed to molding position.

2. A machine for molding an airfoil blade which comprises a pair of maindies having elongated opposed die cavities, the main dies being mountedone above the other, the cavities at one end of the dies having wallsurfaces that diverge at an acute angle to each other, means forreciprocating at least one of the main dies vertically toward and awayfrom the other main die, a substantially vertical track adjacent thediverging wall surfaces of the main die cavities and extending parallelto the direction of reciprocation of the reciprocating main die, anintermediate die mounted for reciprocation on said track, guide membersextending parallel to said track between the main dies to guide themovable main die for movement parallel to movement of the intermediatedie, said intermediate die having a wedge-shaped portion projectingcantilever-fashion between said diverging wall surfaces, the oppositefaces of the wedge-shaped portion being substantially parallel to andadjacent the diverging wall surfaces of the main dies, and a compressionspring extending between the lower main die and the intermediate die,urging the intermediate die to a position between and in spaced relationto the main dies when the main dies are open, the spring yielding whenthe main movable die is closed to molding position.

3. A machine for molding an airfoil blade which comprises a frame, anupwardly facing stationary main die mounted on the frame, a downwardlyfacing movable main die mounted above the stationary main die, the dieshaving elongated opposed die cavities, the cavities at one end of thedies having wall surfaces that diverge at an acute angle to each other,means for reciprocating the movable main die toward and away from thestationary main die, upright guides mounted on the frame for guiding themovable main die, an upright keyway member mounted on the frame adjacentthe diverging end portions of the main die cavities and having a keywayparallel to the guides, an intermediate die member having a die portionand a shank, there being a key on the shank in engagement with thekeyway to guide the intermediate die for reciprocation, the die portionof the intermediate die being wedge-shaped and projectingcantilever-fashion between the diverging wall surfaces, the oppositefaces of the wedge-shaped portion being substantially parallel to andadjacent the diverging wall surfaces of the main dies, and a springurging the intermediate die to a position between and spaced in relationto the main dies when the main dies are open, the spring yielding whenthe main movable die is closed to molding position.

References Cited in the file of this patent UNITED STATES PATENTS

